Agreed. MOTA allows them to shoot with pistols only. It doesnt matter if the opponent chooses models to die who arent within 1" of enemy models. If the unit is within engagement range of any enemy models, they can only use pistols to shoot.
Music of the Apocalypse
Each time a model in this unit is slain, it is driven to make one last attack before succumbing to its injuries. Do not remove the slain model yet - after the attacking unit has finished making all its attacks, the slain model can shoot with one of its ranged weapons as if it were your Shooting phase. The slain model is then removed as a casualty as normal.
LOCKED IN COMBAT
Models cannot make attacks with ranged weapons while their unit is
within Engagement Range of any enemy models (pg 4). Models also
cannot target enemy units within Engagement Range of any other
units from your army – the risk of hitting your own troops is too great.
PISTOL
Due to their compact size, pistols can even be used in
melee to shoot at point-blank range.
A model can make attacks with a Pistol even when its unit is within
Engagement Range of enemy units, but it must target an enemy
unit that is within Engagement Range of its own unit when it does
so. In such circumstances, the model can target an enemy unit even
if other friendly units are within Engagement Range of the same
enemy unit.